A toggle is a switch with two positions — it can be on or off. It can also describe a state of being, such as “being on or off in a relationship.” Toggle is sometimes used as a verb, such as “toggle between screens during a video call with two friends at once.” The term is borrowed from the physical switch found on switches and electrical devices.
Toggles are often paired with checkboxes and radio buttons in HTML code to create accordions and other content structures that expand on a click or hover. A toggle can also be a way of showing or hiding content, such as a question with a hidden answer that is clicked to reveal it.
In programming, a toggle is usually a Boolean variable that can be set to either on or off. The toggle variable is then associated with an event or action and triggered when that event or action occurs. The state of the toggle can then be changed by another trigger, and the process is repeated until the desired state is reached.
A toggle can be a good choice for a design element, but it’s important to avoid using it as a substitute for logic. Instead, use it where necessary to create a consistent experience across pages and avoid confusing users. For example, it’s not a good idea to toggle between two different types of content, such as an article and a blog post.
It’s also a good idea to use a clear, consistent name for a toggle. A meaningful name is especially helpful in automated tests, when it helps developers understand the purpose of a toggle and how to test for it. A toggle named “Lisa’s Blog” is likely to provide a more useful output than a toggle named simply “blog.”
Toggle configuration should live side-by-side in source control, along with the toggle itself, so that it can be easily updated if needed. This is often accomplished by creating a centralized store, such as an existing application DB. This can be augmented with some type of admin UI, to make it easier for system operators, testers and product managers to view and modify the toggle configuration.
When designing toggles, it’s critical to consider the societal and cultural implications of color. For example, relying on red and green to signal state changes can be problematic for some users who have red/green color blindness or other vision issues. It’s a good idea to use high-contrast colors for states and include text or icons to clarify the meaning of each.
While it’s common to use toggles in the context of A/B testing, they can be used for other types of data-driven optimizations as well. For example, an e-commerce company might want to know whether a new recommendation algorithm is more effective than an old one. The company could add an experiment toggle to their production configurator, with the two algorithms, then track user behavior across the cohorts. Once they have conclusive data, they can remove the experiment toggle and deploy the recommended algorithm for all users.
